Global Patent Index - EP 0638139 A4

EP 0638139 A4 19950419 - ENGINE NOx REDUCTION SYSTEM.

Title (en)

ENGINE NOx REDUCTION SYSTEM.

Title (de)

VORRICHTUNG ZUR NOx-REDUKTION VON BRENNKRAFTMASCHINEN.

Title (fr)

SYSTEME DE REDUCTION DES OXYDES NITRIQUES DE MOTEURS-----.

Publication

EP 0638139 A4 19950419 (EN)

Application

EP 92912974 A 19920420

Priority

  • CA 2133572 A 19920420
  • US 9203225 W 19920420
  • US 70149791 A 19910516

Abstract (en)

[origin: US5224346A] A method and apparatus are provided for reducing pollutants and especially nitrogen oxides, or NOx, in the exhaust gases of an engine. The apparatus includes a device for injecting ammonia into a conduit that extends between cylinder exhaust valves and a catalytic converter, to mix the ammonia with the exhaust gases. Ammonia injection occurs at a location a plurality of inches downstream of the exhaust valves to avoid burning of the ammonia by flames. The injection preferably occurs at a location where the exhaust gases are at a temperature of at least about 1200 DEG F. to cause considerable reaction of the ammonia with NOx in the exhaust gases prior to the gases reaching the catalyst, so less NOx must be removed along the catalyst. To minimize ammonia use, it is injected only for a limited period such as a minute after a cold engine is started when the catalyst is too cold to cause significant reactions, and during operation of the engine at high power levels when the greatest amounts of NOx are produced.

IPC 1-7

F01N 3/20

IPC 8 full level

F01N 3/20 (2006.01); F01N 3/36 (2006.01); F02B 1/04 (2006.01)

CPC (source: EP US)

F01N 3/2066 (2013.01 - EP US); F01N 3/36 (2013.01 - EP US); F01N 2610/02 (2013.01 - EP US); F01N 2610/1453 (2013.01 - EP US); F02B 1/04 (2013.01 - EP US); Y02T 10/12 (2013.01 - EP US)

Citation (search report)

Designated contracting state (EPC)

AT BE CH DE DK ES FR GB GR IT LI LU MC NL SE

DOCDB simple family (publication)

US 5224346 A 19930706; CA 2133572 A1 19931028; CA 2133572 C 20021224; EP 0638139 A1 19950215; EP 0638139 A4 19950419; EP 0638139 B1 19970716; WO 9321432 A1 19931028

DOCDB simple family (application)

US 70149791 A 19910516; CA 2133572 A 19920420; EP 92912974 A 19920420; US 9203225 W 19920420